Until now, in the state of the art, three types of ortheses have been proposed for the upper limb: in the first type the various parts of the limb are tightly held in shells which are actuated with respect to each other by means of motor devices controlled by the subject, such as, for instance, an electric motor or an artificial inflatable muscle; in the second type, the limb is supported in a given position by means of a rigid frame; in the third type, the limb is supported by an external rigid structure articulated at several points by pins so as to allow a given mobility of the various parts of the limb with respect to each other but the subject can only control the movements of his limb by an external action, either with an external motor or by an action of his other limb. In all these cases, the limb is entirely supported and the movement of the joints when it does exist, is far more limited than the physiological movement of the joints.
On the contrary, according to the invention, the limb may have all the normal physiological movements, the joints being capable of operating in all the admissible physiological directions and the control of the limb is effected by the subject himself, without the help of an external motor, by operating the scapular motor constituted by the structure of the shoulder. Depending on whether, by the movements of his shoulder, the subject opens or closes the scapular cone constituted at the level of the connection of the shoulderblade and the clavicle, he produces an action on the humerus which, by means of the apparatus according to the invention, results in a set of actions on all the parts of the limb which cause the joints to operate within the constraints of the normal physiological movement.